Nutrient accumulation and role of atmospheric deposition in coniferous stands

Three stand types on drained wetlands, all 31 years old, were studied. The stands were: (1) Scots pine, unfertilized; (2) Scots pine, fertilized; and (3) Norway spruce, fertilized. Amounts of nutrients (N, K, Ca, Mg, P, S, B, Fe, Mn, Zn, Cu) in above-ground biomass for all three stand types could be simulated precisely by a curvilinear regression model, with stand volume on bark as regressor. Net H⁺ production of the fertilized pine was estimated to be 661 mol H⁺ ha^?1 year^?1 from establishment to 31 years of age. The corresponding value for spruce was 1232 mol H⁺ ha^?1 year^?1. Atmospheric inputs to the pine and spruce sites were 695 and 516 mol H⁺ ha^?1 year^?1, respectively. Atmospheric input of N was 2.3 and 1.3 times the accumulation in the biomass of unfertilized and fertilized pine, whereas the value for spruce was 0.7. The corresponding ratios for S were 43, 19, and 11.